Objective: Antibacterial/antifungal tests and synergistic interactions between polyprenols and other lipids(including fifteen known compounds) isolated from Ginkgo biloba leaves against five selected stains (Salmonella enterica

Staphylocococus aureus

Aspergillus niger

Escherichia coli and Bacillus subtilis) were carried out. Method: Antibacterial/antifungal actions and synergistic interactions were observed using a disc-diffusion method at 500 mg·L-1 in n-hexane(blank) by measuring inhibition halos and comparing minimum inhibitory concentrations(MIC)

minimal bactericidal concentration(MBC)

minimal fungicidal concentration(MFC) values by recording the sample concentration(250

125

62.5

31.3

15.6

7.8

3.9 mg·L-1 in n-hexane)as no bacteria growing and figuring out fractional inhibitory concentration(FIC) Index. Result: Nerolidol showed the highest activity against the four tapes of bacteria(S. enterica

S. aureus

E. coli and B. subtilis) among all the tested samples

and inhibition halos were 17.4-20.9 mm

MIC and MBC values were the range of 3.9- 15.6

31.3-62.5 mg·L-1. linalool showed the highest activity against A. niger among all the tested samples and the GBP with β-caryophyllene mixture group had the strongest synergistic effect against B. subtilis among all mixture groups against the five tested strains

and inhibition halos were 17.9 mm

MIC and MFC values were 7.8

31.3 mg·L-1. The proportion of β-caryophyllene and GBP was 43.42%:56.58% that was determinated by Mixture Design as the optimal proportion of synergistic effect on GBP with isophytol against B. subtilis. In the meantime

the truth values of FIC index and inhibition halos were respectively 0.16

19.8 mm. Conclusion: G. biloba leaves polyprenols and other lipids have antimicrobial effects and the parts of lipid compounds with polyprenols have synergistic effects against the tested strains.